Until recently, there were two genera in the ectomycorrhizal fungi in the Russulaceae: Lactarius and Russula. Now there are four genera in the Russulaceae: Lactifluus, Lactarius, Multifurca and Russula. Why? Because some species in both Russula and Lactarius were found to have a different evolutionary history. Most species of Lactifluus are tropical, although we do have several common and recognizable species in the temperate zone. Lactifluus mushrooms share the characterisitics of not having zonate or viscid caps. They are are often velvety and many of the ones in the tropics have veils.